Use DescribeVoices com um AWS SDK

    using System;
    using System.Threading.Tasks;
    using Amazon.Polly;
    using Amazon.Polly.Model;

    public class DescribeVoices
    {
        public static async Task Main()
        {
            var client = new AmazonPollyClient();

            var allVoicesRequest = new DescribeVoicesRequest();
            var enUsVoicesRequest = new DescribeVoicesRequest()
            {
                LanguageCode = "en-US",
            };

            try
            {
                string nextToken;
                do
                {
                    var allVoicesResponse = await client.DescribeVoicesAsync(allVoicesRequest);
                    nextToken = allVoicesResponse.NextToken;
                    allVoicesRequest.NextToken = nextToken;

                    Console.WriteLine("\nAll voices: ");
                    allVoicesResponse.Voices.ForEach(voice =>
                    {
                        DisplayVoiceInfo(voice);
                    });
                }
                while (nextToken is not null);

                do
                {
                    var enUsVoicesResponse = await client.DescribeVoicesAsync(enUsVoicesRequest);
                    nextToken = enUsVoicesResponse.NextToken;
                    enUsVoicesRequest.NextToken = nextToken;

                    Console.WriteLine("\nen-US voices: ");
                    enUsVoicesResponse.Voices.ForEach(voice =>
                    {
                        DisplayVoiceInfo(voice);
                    });
                }
                while (nextToken is not null);
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: " + ex.Message);
            }
        }

        public static void DisplayVoiceInfo(Voice voice)
        {
            Console.WriteLine($" Name: {voice.Name}\tGender: {voice.Gender}\tLanguageName: {voice.LanguageName}");
        }
    }

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.polly.PollyClient;
import software.amazon.awssdk.services.polly.model.DescribeVoicesRequest;
import software.amazon.awssdk.services.polly.model.DescribeVoicesResponse;
import software.amazon.awssdk.services.polly.model.PollyException;
import software.amazon.awssdk.services.polly.model.Voice;
import java.util.List;

/**
 * Before running this Java V2 code example, set up your development
 * environment, including your credentials.
 *
 * For more information, see the following documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */
public class DescribeVoicesSample {
    public static void main(String args[]) {
        PollyClient polly = PollyClient.builder()
                .region(Region.US_WEST_2)
                .build();

        describeVoice(polly);
        polly.close();
    }

    public static void describeVoice(PollyClient polly) {
        try {
            DescribeVoicesRequest voicesRequest = DescribeVoicesRequest.builder()
                    .languageCode("en-US")
                    .build();

            DescribeVoicesResponse enUsVoicesResult = polly.describeVoices(voicesRequest);
            List<Voice> voices = enUsVoicesResult.voices();
            for (Voice myVoice : voices) {
                System.out.println("The ID of the voice is " + myVoice.id());
                System.out.println("The gender of the voice is " + myVoice.gender());
            }

        } catch (PollyException e) {
            System.err.println("Exception caught: " + e);
            System.exit(1);
        }
    }
}

class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def describe_voices(self):
        """
        Gets metadata about available voices.

        :return: The list of voice metadata.
        """
        try:
            response = self.polly_client.describe_voices()
            self.voice_metadata = response["Voices"]
            logger.info("Got metadata about %s voices.", len(self.voice_metadata))
        except ClientError:
            logger.exception("Couldn't get voice metadata.")
            raise
        else:
            return self.voice_metadata

require 'aws-sdk-polly' # In v2: require 'aws-sdk'

begin
  # Create an Amazon Polly client using
  # credentials from the shared credentials file ~/.aws/credentials
  # and the configuration (region) from the shared configuration file ~/.aws/config
  polly = Aws::Polly::Client.new

  # Get US English voices
  resp = polly.describe_voices(language_code: 'en-US')

  resp.voices.each do |v|
    puts v.name
    puts "  #{v.gender}"
    puts
  end
rescue StandardError => e
  puts 'Could not get voices'
  puts 'Error message:'
  puts e.message
end

async fn list_voices(client: &Client) -> Result<(), Error> {
    let resp = client.describe_voices().send().await?;

    println!("Voices:");

    let voices = resp.voices();
    for voice in voices {
        println!("  Name:     {}", voice.name().unwrap_or("No name!"));
        println!(
            "  Language: {}",
            voice.language_name().unwrap_or("No language!")
        );

        println!();
    }

    println!("Found {} voices", voices.len());

    Ok(())
}